Answer: -
2.5 moles of calcium atoms are in 2.5 moles of calcium carbonate CaCO₃
Explanation: -
In order to solve such types of problems, the first step would be to write the chemical formula of the compound.
The chemical formula of calcium carbonate = CaCO₃
The chemical symbol of Calcium is Ca.
From the formula of calcium carbonate we can see that
1 mole of CaCO₃ has 1 mole of Ca
2.5 mole of CaCO₃ has 
= 2.5 mol of Ca.
∴2.5 moles of calcium atoms are in 2.5 moles of calcium carbonate CaCO₃
Answer:
CH₄ will diffuse at faster rate.
Explanation:
According to Graham's law,
The rate of diffusion is inversely proportional to the square root of molar mas of gas.
It is given in question the molar mass of CH₄ is 16 g. Thus the square rot of 16 is.
√16 = 4
The molar mass of SO₂ is 64 g and the square root is,
√64 = 16
As it is stated that diffusion rate is inversely related to the square root of molar mass thus the diffusion rate of SO₂ is lower while methane diffuse faster.
The answer is - ide.
That is how you name the anions in a ionic compound, you replace the ending of the name of the element with ide.
Some examples:
Ionic compound anion name of the anion
NaCl Cl- chloride
KF F- fluoride
NaI I- iodide
CaBr2 Br- bromide
Answer:
The electron stays in an excited state for a short time. When the electron transits from an excited state to its lower energy state, it will gice off the same amound of energy needed to raise to that level. This emitted energy is a photon.
I think it’s C is the answer
I hope it helps you
